| Autor: |
Kartick C. Sarkar, Santanu Mondal, Prateek Sharma, Tsvi Piran |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
The Astrophysical Journal, Vol 951, Iss 1, p 36 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
1538-4357 |
| DOI: |
10.3847/1538-4357/acd75d |
| Popis: |
One of the leading explanations for the origin of Fermi Bubbles is past jet activity in the Galactic center supermassive black hole Sgr A ^* . The claimed jets are often assumed to be perpendicular to the Galactic plane. Motivated by the orientation of pc-scale nuclear stellar disk and gas streams, as well as a low inclination of the accretion disk around Sgr A ^* inferred by the Event Horizon Telescope, we perform hydrodynamical simulations of nuclear jets significantly tilted relative to the Galactic rotation axis. The observed axisymmetry and hemisymmetry (north–south symmetry) of Fermi/eROSITA bubbles (FEBs) due to quasi-steady jets in Sgr A ^* could be produced if the jet had a super-Eddington power (≳5 × 10 ^44 erg s ^−1 ) for a short time (jet active period ≲6 kyr) for a reasonable jet opening angle (≲10°). Such powerful explosions are, however, incompatible with the observed O viii /O vii line ratio toward the bubbles, even after considering electron–proton temperature nonequilibrium. We argue that the only remaining options for producing FEBs are (i) a low-luminosity (≈10 ^40.5−41 erg s ^−1 ) magnetically dominated jet or accretion wind from the Sgr A ^* , or (ii) a supernovae or tidal disruption event driven wind of a similar luminosity from the Galactic center. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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